Winco PSS20000/C - Manual (Page 8)

PAGE 6
Natural Gas
1 3 4
UNIT OFF LINE PSI 7-11 in 7-11 in
4-6 oz 4-6 oz
STARTING LINE PSI 7-11 in 7-11 in
4-6 oz 4-6 oz
NO LOAD LINE PSI 7-11 in 7-11 in
4-6 oz 4-6 oz
FULL LOAD LINE PSI 7-11 in 7-11 in
4-6 oz 4-6 oz
LP LIQUID WITHDRAWAL
The following is a block diagram of a typical L/P Liquid
Withdrawal fuel system for the PSS20000.
Tank Fuel Solenoid Converter Engine
1 2 3 4
Reference number 1 is the fuel tank. No regulator is
required but the tank must have a liquid withdrawal drop
tube installed in it and a liquid valve on the tank.
Reference number 2 through 4 are installed on the
engine generator set.
Liquid fuel is delivered from the tank directly to the fuel
solenoid on the generator at full tank pressure. This
system requires no pressure regulator be installed any
where in the system. The converter mounted on the
engine generator set will take the liquid fuel at tank
pressure and convert it to vapor at the proper delivery
rate.
LP/NG FUEL ADJUSTMENTS
**** CAUTION ****
Do not make any fuel adjustments or governor adjust-
ments until all pressure readings are in compliance with
specification. See fuel pressure charts (tables 1, 2, and
3).
NATURAL GAS (NG)
Due to variations in NG fuel characteristics and BTU
levels throughout the country, it may be necessary to
readjust the fuel mixture once the engine has been
installed and serviced.
**** CAUTION ****
Never make a fuel mixture adjustment on a unit when it is
stopped or running no load. A mixture adjustment is only
effective when the engine is operating under load.
ADJUSTMENT PROCEDURE
1. Insure the unit is operating with an 80 to 100% load
or at the highest anticipated load.
2. Attach a frequency meter to monitor Hz.
Note: The fuel mixture adjustment on the PSS8000 is
the brass load block located on top of the demand
regulator. This load block is a multi-turn needle
valve. On the PSS20000 & PSS12000 it is located on
the carburetor just behind the fuel inlet hose. This
mixture adjustment is a partial turn, lean to rich, load
block.
3. Begin making a mixture adjustment, observing the Hz
meter. If the meter begins to drop you have the mixture
set too lean or to rich . Adjust the valve in the opposite
direction. Adjustments should be made very slowly.
Adjust back and forth until the highest Hz is achieved. Do
not turn the valve richer after the Hz quits rising, this
would cause the engine to run rich. If the Hz is out of
upper or lower limits, a governor adjustment will be
necessary.
4. On the PSS8000 & PSS12000 see your engine
manual for governor adjustment procedures. The
PSS20000 is equipped with an electronic governor which
requires no adjustment.
**** CAUTION ****
Under full load do not adjust the Hz above 60. If a higher
Hz reading is used, as the load is decreased the Hz will
go out of upper limits (61 to 62 Hz).
PROPANE (LP)
A generator set factory tested on LP will normally
require no adjustment. If for some unforeseen reason
the machine should require adjustment, follow the NG
procedure.
FUEL TYPE CONVERSION
If it should be necessary to change the type of fuel used
after a unit is received, the following procedures are
provided.
PSS8000
These units require no changes to the regulator. After
plumbing in the fuel lines the only thing necessary is to
reset your mixture as detailed in the adjustment section
above.
PSS12000 & PSS20000
NATURAL GAS TO PROPANE
1. Turn off fuel supply.
2. Remove the fuel line from the carburetor at the
demand regulator.
3. Remove the cap on the upright column of the
regulator. This will expose the pressure spring adjusting
screw. Back off the spring adjusting screw so there is
just enough room to replace the cover. Replace the cover
4. Invert the regulator so it is positioned with the column
pointing down.
5. Reconnect the fuel line at the regulator.
6. Remove the 1/8 NPT plug (the one closest to fuel
solenoid) located on what is now the top of the regulator.
Connect a fuel pressure meter or a manometer where